John Elliott Jr. has died at 84.

He landed his first job in advertising in 1945 as a copywriter at what was then Batten, Barton, Durstine & Osborn, now the BBDO Worldwide division of the Omnicom Group. He joined Ogilvy in 1960 to run the newly acquired Shell Oil Company account and quickly began his ascent at the agency. He retired as chairman of Ogilvy & Mather International in 1982.

"Big ideas are so hard to recognize, so fragile, so easy to kill," Mr. Elliott said in announcing his retirement at the agency's annual meeting in December 1981. "Don't forget that, all of you who don't have them."

Mr. Elliott's dry wit and self-deprecating sense of humor were staples of the many speeches he delivered at advertising industry events. Looking back on his early days as a copywriter, he once said: "I was pretty good, but not good enough. I could execute campaigns, but never came up with the big ideas, so I went into a less demanding kind of work. I became an account man."